• The Korean Journal of Physiology and Pharmacology
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• 제10권4호
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• pp.181-186
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• 2006

This study was undertaken to evaluate whether peroxisome proliferator-activated-receptor-gamma $(PPAR-{\gamma})$ agonist-rosiglitazone (ROSI) induces postischemic functional recovery in Langendorf heart model. Hearts isolated from normal rats were subjected to 20 min of normoxia or 25 min zero-flow ischemia followed by 50 min reperfusion. In this acute protocol, ROSI $(20\;{\mu}g/ml)$ administered 10 min before ischemia had no effect on hemodynamic cardiac function, but had protective effect on lipid peroxidation in in vitro experiments. In chronic protocol in which ROSI was given by daily gavage (4 mg/kg) for three consecutive days, ROSI could not prevent the hemodynamic alteration on cardiac performance, but has protective effect on the activity of superoxide dismutase (SOD). There was no significant difference in the contents of reduced glutathione (GSH) and catalase activity between ischemia-reperfusion (IR) and ROSI treated IR hearts. Although ROSI had no effect on hemodynamic factor, it had effect on antioxidant activity. Our results indicate that ROSI provides partial beneficial effects by inhibiting lipid peroxidation and/or recovering normal level of SOD activity in the ischemic reperfused heart.

• Preventive Nutrition and Food Science
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• 제18권1호
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• pp.38-44
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• 2013

The protective effect of Polyopes lancifolia extract on high glucose-induced oxidative stress was investigated using human umbilical vein endothelial cells (HUVECs). High concentration of glucose (30 mM) treatment induced HUVECs cell death, but Polyopes lancifolia extract, at concentrations of 25, 50, and $100{\mu}g/mL$, protected cells from high glucose-induced damage. Furthermore, thiobarbituric acid reactive substances, intracellular reactive oxygen species, and nitric oxide levels increased by high glucose treatment were effectively decreased by treatment with Polyopes lancifolia extract in a dose-dependent manner. Also, Polyopes lancifolia extract treatment reduced the overexpressions of inducible nitric oxide synthase, cyclooxygenase-2, and nuclear factor-kappa B proteins activation that was induced by high glucose in HUVECs. These results indicate that Polyopes lancifolia extract is a potential therapeutic material that will reduce the damage caused by high glucose-induced-oxidative stress associated with diabetes.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.760-763
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• 2003

We have investigated the electro-optical characteristics of image sticking in AC PDP. Although Image sticking is one of major factors to determine display quality in AC PDP, so far, it has not being reported why it is occurred and how we can prevent it. In this experiment, we have analyzed the effect of MgO protective layer and phosphor on the image sticking and we have measured the difference of firing voltage, brightness and discharge current between sticking image and normal image in AC PDP. As a result, Phosphor degradation is a more major factor than MgO protective layer and the firing voltage of gas discharge in sticking image is higher than that of normal discharge.

• Journal of Ginseng Research
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• 제34권2호
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• pp.145-149
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• 2010

This study investigated the antioxidant effects of ginseng coffee in L6 muscle cells. Ginseng coffee was prepared by coating and digesting coffee beans with ginseng concentrate. The ginseng coffee water extract potently protected against hydrogen peroxide-induced L6 cell death and adenosine triphosphate reduction in a dose-dependent manner; in fact, these cytoprotective effects were significantly greater than those of normal coffee. However, ginseng coffee did not exhibit significant radical scavenging or catalase-like activity. These results suggest that ginseng coffee might act as a cytoprotective agent in muscles, but that the protective effects are not due to a direct radical-reduction property but rather to another intracellular signaling factor.

• 대한한의학회지
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• 제21권1호
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• pp.91-98
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• 2000

The water extract of Seongpungtang(SPT) has commonly been used for treatment of ischemic brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extract of SPT rescues brain cells from ischemic damage. To elucidate the protective mechanism of ischemic induced cytotoxicity, the regulation of Lipopolysaccharide (LPS) and PMA (phobol-12-myristate-13-acetate) induced iNOS expression in microglial cells was investigated. LPS and PMA treatment for 48 hr in microglial cells markedly induced nitric oxide (NO), but treatment of the cells with the water extract of SPT decreased nitrite formation. In addition, LPS and PMA treatment for 48 hr induced severe cell death in microglial cells. However treatment of the cells with the water extract of SPT did not induce significant changes compared to the control cells. Furthermore, NO production was markedly decreased by treatment of nuclear factor kappa B(NF-kB) inhibitor, pyrrolidine dithiocarbamate(PDTC). According to the above results, it is suggested that the protective effects of the water extract of SPT against ischemic brain damage may be mediated by regulation of iNOS during ischemic condition.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제49권9호
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• pp.527-532
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• 2000

The performance of ac plasma display panels (PDP) is influenced strongly by the surface glow discharge characteristics on the MgO thin films. This paper deals with the surface glow discharge characteristics and some physical properties of MgO thin films prepared by reactive RF planar unbalanced magnetron sputtering in connection with ac PDP. The samples prepared with dc bias voltage of -10V showed lower discharge voltage and lower erosion rate byion bombardment than those samples prepared by conventional magnetron sputtering or E-beam evaporation. The main factor that improves the discharge characteristics by bias voltage is considered to be due to the morphology changes or crystal structure of the MgO thin film by ion bombardement during deposition process.

• 전기학회논문지
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• 제67권9호
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• pp.1141-1145
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• 2018

Generally, in nuclear plants, distance relay (21R) has adapting to protect and to operate main protective of transmission lines and backup protective of main generator. Operation of 21R was required and based on exactly accurate calculation and criteria. But presently method of 21R setting has applied according to protection devices operation guide of KPX, excepting IEEE and ISA standards, which have a difference review directions, consider parameters and devices, also consideration factors were affected to relay operations by uncertain guides. therefore this paper proposed new protection relay setting method and unvague criteria from IEEE 741 and ANSI/ISA 67.04.01, and reviewed a different results through numerical calculation results for methods and criteria including previous and established 21r setting by IEEE, ANSI/ISA Technical standards.

• 아동학회지
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• 제26권1호
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• pp.329-345
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• 2005

Gender and intelligence of children, parenting practices and socioeconomic status of parents were studied to investigate whether they functioned as protective factors for resilient children. Total of 556 children of 12 years of age were contacted for the study. Teachers were asked to rate the children's interpersonal competence. Children reported their experience of stressful life events on a checklist. Based on the competence scores and the experience of stressful life events, 107 children were classified into adaptive, resilient, and maladaptive group. IQ scores were assessed using an intelligence test for the 107 children. Mothers reported their parenting practices and their socioeconomic status through a questionnaire. Descriptive statistics, chi-squares, t-tests, and one-way ANOVAs were performed to analyze the data. There was no difference in their experience of stressful life events between boys and girls. Girls were rated as being more competent by their teachers. There were more girls in the adaptive and the resilient group and more boys in the maladaptive group. Children in adaptive and the resilient group had higher intelligence scores than the maladaptive group. Mothers of resilient children replied as being warm and acceptive and more refusing and controlling than mothers of the adaptive children Group differences in socioeconomic status of the family were not found. Thus, being a girl and having higher IQ scores were the protective factors for the resilient children.

• 사회복지연구
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• 제37호
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• pp.399-427
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• 2008

본 연구는 비행친구와의 교류가 청소년기 비행에 미치는 영향을 보호요인이 완충하고 있는지를 확인하고자 하였다. 비행친구와의 교류는 청소년기 비행을 유발하는 주요한 위험요인으로 제시되고 있다. 보호요인은 위험요인의 부정적 영향을 완화 완충시켜주는 역할을 하는데, 자아존중감과 부모애착, 부모의 지도감독은 비행의 발생을 막는 주요한 보호요인이다. 이에 높은 보호요인을 가지고 있는 경우 위험요인인 비행친구와의 교류가 비행에 미치는 영향이 감소하거나 사라지는지를 상호작용효과모형을 통해 알아 보았다. 분석자료로는 전국규모의 종단조사자료인 한국청소년패널자료를 이용하였다. 분석결과, 성별에 따라 비행친구와의 교류가 미치는 영향을 완충하는 보호요인의 효과는 상이한 것으로 나타났다. 여자청소년의 경우, 자아존중감, 부모애착, 지도감독은 모두 위험요인의 영향을 완충하는 조절효과를 갖는 것으로 나타났다. 반면 남자청소년에게서 보호요인의 조절효과는 확인되지 않았다. 성별에 따라 보호요인의 상이한 조절효과가 나타난 결과에 근거하여 실천적, 정책적 함의를 살펴보았고, 필요한 후속연구의 과제에 대해 제시하였다.

• 대한본초학회지
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• 제37권4호
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• pp.1-8
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• 2022

Objectives : Dioscorea batas Decaisne (DB) has been known to be good for the digestive system on Eastern Asia. However, the protective effect of DB on acute pancreatitis (AP) has not been studied. In this study, we tried to investigate the protective effect of DB water extract on caerulein-induced AP. Methods : To measure the protective effect of DB on AP, Mice were injected with cholecystokinin analogue caerulein (50 ㎍/kg) hourly for 6 times. DB water extract (200 or 400 mg/kg) or saline (control group) was administered orally 1 h before the first injection of caerulein. The mice were sacrificed at 6 h after the last injection of caerulein. The pancreas tissues and serum samples were immediately taken for further analysis. Results : Administration of DB water extract showed the inhibitory effect on the increase of pancreas weight/body weight ratio, pancreatic histological damage. And the rise of serum lipase level was significantly reduced in DB water extract treatment group during AP in mice. However administration of DB water extract did not show significant reduction in serum amylase level. Also, mRNA levels of pro-inflammatory cytokines Interleukin (IL)-6 and Tumor necrosis factor (TNF)-𝛼 but not IL-1𝛽 were inhibited by administration of DB water extract. Conclusions : Taken together, we found that administration of DB water extract ameliorates the severity of caerulein-induced AP, which suggests the potential to be an effective treatment on AP.